/Engine/Source/Editor/BlueprintGraph/Public/BlueprintActionDatabase.h
Each node spawner is categorized by a class orasset. A spawner that corresponds to a specific class field (like a function, property, enum, etc.) will be listed under that field's class owner. Remaining spawners that can't be categorized this way will be registered by asset or node type.
The entire action database, which maps specific objects to arrays of associated node-spawners.
[FActionRegistry](API\Editor\BlueprintGraph\FBlueprintActionDatabase\FActionRegistry) const & GetAllActions()